Re: [PATCH v4 01/15] crypto: accumulative hashing API

[Daniel P . Berrangé]

On Wed, Aug 07, 2024 at 07:51:08PM +0000, Alejandro Zeise wrote:
> Changes the hash API to support accumulative hashing.
> Hash objects are created with "qcrypto_hash_new",
> updated with data with "qcrypto_hash_update", and
> the hash obtained with "qcrypto_hash_finalize".
> 
> These changes bring the hashing API more in line with the
> hmac API.
> 
> Signed-off-by: Alejandro Zeise <alejandro.zeise@seagate.com>
> ---
>  crypto/hashpriv.h     |  13 +++++
>  include/crypto/hash.h | 119 ++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 132 insertions(+)
> 
> diff --git a/crypto/hashpriv.h b/crypto/hashpriv.h
> index cee26ccb47..02f17ee99f 100644
> --- a/crypto/hashpriv.h
> +++ b/crypto/hashpriv.h
> @@ -1,6 +1,7 @@
>  /*
>   * QEMU Crypto hash driver supports
>   *
> + * Copyright (c) 2024 Seagate Technology LLC and/or its Affiliates
>   * Copyright (c) 2017 HUAWEI TECHNOLOGIES CO., LTD.
>   *
>   * Authors:
> @@ -15,6 +16,8 @@
>  #ifndef QCRYPTO_HASHPRIV_H
>  #define QCRYPTO_HASHPRIV_H
>  
> +#include "crypto/hash.h"
> +
>  typedef struct QCryptoHashDriver QCryptoHashDriver;
>  
>  struct QCryptoHashDriver {
> @@ -24,6 +27,16 @@ struct QCryptoHashDriver {
>                         uint8_t **result,
>                         size_t *resultlen,
>                         Error **errp);
> +    QCryptoHash *(*hash_new)(QCryptoHashAlgorithm alg, Error **errp);
> +    int (*hash_update)(QCryptoHash *hash,
> +                       const struct iovec *iov,
> +                       size_t niov,
> +                       Error **errp);
> +    int (*hash_finalize)(QCryptoHash *hash,
> +                         uint8_t **result,
> +                         size_t *resultlen,
> +                         Error **errp);
> +    void (*hash_free)(QCryptoHash *hash);
>  };
>  
>  extern QCryptoHashDriver qcrypto_hash_lib_driver;
> diff --git a/include/crypto/hash.h b/include/crypto/hash.h
> index 54d87aa2a1..6d7222867e 100644
> --- a/include/crypto/hash.h
> +++ b/include/crypto/hash.h
> @@ -1,6 +1,7 @@
>  /*
>   * QEMU Crypto hash algorithms
>   *
> + * Copyright (c) 2024 Seagate Technology LLC and/or its Affiliates
>   * Copyright (c) 2015 Red Hat, Inc.
>   *
>   * This library is free software; you can redistribute it and/or
> @@ -25,6 +26,13 @@
>  
>  /* See also "QCryptoHashAlgorithm" defined in qapi/crypto.json */
>  
> +typedef struct QCryptoHash QCryptoHash;
> +struct QCryptoHash {
> +    QCryptoHashAlgorithm alg;
> +    void *opaque;
> +    void *driver;
> +};
> +
>  /**
>   * qcrypto_hash_supports:
>   * @alg: the hash algorithm
> @@ -120,6 +128,117 @@ int qcrypto_hash_digestv(QCryptoHashAlgorithm alg,
>                           char **digest,
>                           Error **errp);
>  
> +/**
> + * qcrypto_hash_updatev:
> + * @hash: hash object from qcrypto_hash_new
> + * @iov: the array of memory regions to hash
> + * @niov: the length of @iov
> + * @errp: pointer to a NULL-initialized error object
> + *
> + * Updates the given hash object with all the memory regions
> + * present in @iov.
> + *
> + * Returns: 0 on success, non-zero on error

Minor point, this and all the other APIs should be saying
'or -1 on error' to follow QEMU's error reporting standards.


With regards,
Daniel
-- 
|: https://berrange.com      -o-    https://www.flickr.com/photos/dberrange :|
|: https://libvirt.org         -o-            https://fstop138.berrange.com :|
|: https://entangle-photo.org    -o-    https://www.instagram.com/dberrange :|